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Arch Bridges need to be able to support the weight, also called the load, of the
objects (people, cars, trucks, etc.) on it. Therefore, the structure underneath the bridge
needs to be able to get the job done. The underside of bridges looks different when
you are comparing different types, and the arch bridge has perhaps one of the most
architecturally distinctive undersides. You see, arch bridges have a curved underside.
It looks like someone cut a semicircle out of the bottom of the bridge.
Arch bridges are some of the most beautiful bridges in the world. Come and learn
about what arch bridges are, their history, real world examples and pros and cons of
this bridge type.Bridges provide a very important function in allowing easy transport
over a body of water, and they look good doing it! While there are several types of
bridges, one of the oldest is the arch bridge. Bridges need to be able to support the
weight, also called the load, of the objects (people, cars, trucks, etc.) on it. Therefore,
the structure underneath the bridge needs to be able to get the job done.
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Beam Bridge
Do you enjoy building structures with toy blocks? Most kids enjoy stacking toy
blocks into creative shapes to build houses, toy cars and even bridges. Typically,
when children build a toy bridge, they take two blocks and stand them straight up and
down in a vertical position. Then, they place one horizontal block across the top of
the two vertical blocks. This set of blocks is designed similar to a beam bridge.
A beam bridge is a bridge that is made of two or more strong towers that support
one or more horizontal beams, or long sturdy pieces of wood or metal.

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Who Designs Beam Bridges?
Engineers are scientists who design beam bridges, among other structures. They
must be very smart and talented in the areas of math and science to design and
oversee the construction of beam bridges. Engineers have to think about a variety of
factors when designing a beam bridge. Some questions they ask themselves include:
• 
Will the beam bridge be short or long?
• 
Will the beam bridge be designed for people to walk or bicycle across?
• 
Will cars and enormous 18-wheel trucks travel over it?
• 
Will it go over water?
• 
What is the climate in the area where the beam bridge will be located?
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